Treating mineral oil



Patented Feb. 13, 1940 v t i 2,189,844

uNiTen STATES f PATENT OFFICE.

TREATING MINERAL OIL John V. Starr and Gustav A. Beiswenger, Eliza-'beth, N. J., assignors to Standard Oil Development Company, acorporation of Delaware No Drawing. Application October 18, 1933, SerialNo. 694,034

9 Claims. (01. 196-113) This invention relates to the art of treatingfractionation. The solvent layer contains the exmineral oils with aselective solvent for the protracted undesirable constituents and issegreduction of high quality lubricating oils and more gated therefromby means of distillation and especially to the treatment of thosefractions, fractionation. The treating may be carried out eitherdistillates or residues, which contain ap either continuously or inbatch. Often it is ad 5' preciable amounts of asphalt-i0 material. Thevantag'cous to divide the solvent mixture into main objectof theinvention is the prevention of eve portions and treat the mineral 011with emulsification when asphalt-containing mineral these port o inSuccessive a oils are treated with selective solvents. This and Theamount of he added s lv t m y ry 10 related objects will be more fullyunderstood from considerably, S y from 5 to as much t the followingdescription. we have found 20-25% to be satisfactory. The

As is well known, phenol is an excellent sel added solvent must have aspecific gravity higher tive solvent for the purification of lubricatingoil than 1. Halogenated derivatives of ethylene. distillates. Its mainaction consists in. the elimit benzene, 6150-, are especially p ednation from the distillate, by means of selective 58 as dd Solvent:- hfollowing Solvents 1 solution, of certain undesirable constituents WhllSed admixture With phenol Showed which cause a rapid decrease ofviscosity as the characteristics as listed below? temperature isincreased. It also removes from the distillate sulfur compounds, carbon,unstable Solvency p fractions and other undesirable constituents. If ior a p grav' Selectmty 20" the charge stock contains appreciable amountsmy of asphaltic material it tends to emulsify with Halogen compounds thesolvent and makes stratification extremely oeybontetrsehlriie. Good1.595 Fair. difficult, if not impossible. Furthermore, when gggj ggg ggfgi '-----g----- egg the oil to be treated is of high specific gravityand Tetrachlorethanewj. T ::::do::: 11 600 Excellent 25 mews" theSeparation Of purified 011 layer Striat d-ea: 31138:: 1:58 titties.

from the solvent layer is neither rapid nor complete. The conditions aresimilar with other selective solvents such as furfural (furfurylalcohol,

As other solvents for asphalt ethylene dibromide, brombenzene, etc. maybe mentioned, di-' nilin et.. 2 8 g g g g ig i ,g i phenyl ether,further h1gh spec fic grav1ty ta r Q the treatlgent of hiavy i if i g soVen s or bases (orgamc bases) such as qu nollne, organic- We havediscovered that selective solvents, es- 2:5 recovered fromcahfonna typepeimliums pecially those having a specific gravity of less h h thanabout 1 may be successfuly used for the B term tar bases. 18 mtendefl Le l 5" the basic compounds derived by extraction or treatment ofasphalt-containing mineral 0115 if wood bar or coal tar with mineralacids it being another high speclfic gravity organic compound understoodof course that bases having a havlng a high solvent action for theasphalt is f d m at r th 1 b added to the selective solvent. The Dreerre Spec y g e e an may 9 game as separated by any suitable means frommixtures phalt solvent should have a specific gravity high- 40 er thanthat of water. If the oil is treated with contammg m such a solvent.mixture the tendency to emulsify The following examples W111 Illustrateour is reduced. The use of an. added solvent with l high specificgravity promotes rapid stratifica- A mlxture of Oklahoma (my and Burbanktion. Also, if the added component is itself a crude was reducedby fireand Steam m resid selective solvent for unsaturates, the selectivityamounting to 43% of h crude and having of the mixture is not impairedand high yields a gravity of flash viscosity of purified 11 are btSaybolt at 210 F. 68 seconds and viscosity in- The solvent mixture isusedin exactly the same dex of 71. This was treated with 2 dumps eachmanner for the treatment of mineral oils as the 100% by volume at 100 F.with a mixed solvent 50 simple selective solvent. The oil to be treatedis comprising 4 parts by volume of phenol and 1 agitated with thesolvent mixture, then allowed part by volume of. mono-chlor benzene. The

to settle and the oil layer is separated from the major portion of theasphaltic material settled to solvent layer. The oil layer contains somesolvent the bottom layer with the extracted (naphthenic) which isremoved by means of distillation and oil. The treated oil layer was thenfurther treat- 55 ed with two dumps each 100% by volume of phenol at 150F. Stratification of the mixture into extract and treated oil layers Wasrapid and complete. The treated oil was then stripped of phenol byvacuum distillation, reduced to the viscosity of the charge stock anddecolorized by contact filtration with activated clay. The productamounted to 65% of the original charge stock and showed the followinginspections:

Gravity 29.5 A. P. I. Flash 400 F. Viscosity, Saybolt at 210 F 69Viscosity index 104 Conradson carbon residue 0.51% Color, Robinson 3Pour 65 F.

Deep Sand Reagan crude was reduced by fireand steam to a residual of 243A. P. I. gravity,

was then stripped of phenol by vacuum distillation, and decolorized bycontact filtration with an activated 019.5. A yield of 75% of treatedoil was obtained. This was dewaxed giving a finished oil of:

Gravity 28.3 A. P. I. Flash 505 F. Viscosity, Saybolt at 210 F 99Viscosity index 101 Color, Robinson 1%;

Pour 45 F.

Our process may be modified in different ways; thus, for example, amixture of two or more high specific gravity organic solvents may beused as the added solvent, also the asphalt solvent may be addeddirectly to a particular stage of the treater. Other modifications willbe apparent to those skilled in the art. Our invention is not to belimited by the examples given for illustration, but only by thefollowing claims in which it is our intention to claim all noveltyinherent in the process.

What we claim is:

1. Process of treating mineral oil, containing asphalt which comprisesagitating the oil with a solvent mixture comprising a solvent having aselective solvent action on certain undesirable constituents which causea rapid decrease of viscosity as the temperature is increased, saidsolvent being selected from the group consisting of phenol, furfural,furfuryl alcohol and aniline, and also comprising about 5 to 50% of ahalogenated hydrocarbon having a specific gravity greater than 1,allowing the formation of two layers, separating the oil layer from thesolvent layer and removing any dissolved solvent from the oil layer toobtain a treated oil.

2. The process of treating mineral oil containing asphalt, whichcomprises extracting same with a mixture comprising a selective solventof the phenol type and a halogenated hydrocarbon having a specificgravity higher than 1.

3. Process according to claim 2 in which the solvent mixture consists ofphenol and chlorbenzene.

4. The process of treating mineral oil cori taining asphalt for thepreparation of lubricating oils, which comprises treating the oil atleast once with a solvent consisting of a major proportion of phenol anda minor proportion of a halogenated hydrocarbon having per se a goodsolvency for asphalt and a specific gravity greater than 1, allowing theformation of two layers, separating the oil layer from the solvent layerand removing any dissolved solvent from the oil layer to obtain atreated oil.

5. The process of treating mineral oil containing asphalt whichcomprises extracting the same with a mixture consisting of phenol andtetrachlorethane.

6. The process of treating mineral oil containing asphalt for thepreparation of lubricating oils, which comprises treating the oil at atemperature of about 100 F. at least once with a solvent consisting of amajor proportion of phenol and a minor proportion of halogenatedhydrocarbon having per se a good solvency for asphalt and a specificgravity greater than 1, allowing the formation of two layers, separatingthe oil layer from the solvent layer, removing any dissolved solventfrom the oil layer to obtain a treated oil, and subjecting the treatedoil to at least one additional treatment with a selective solvent of thephenol type at a more elevated temperature.

7. The process of treating a residual asphaltcontaining fraction ofpetroleum which comprises extracting the same with a mixture comprisinga selective solvent of the phenol type and a halogenated hydrocarbonhaving a specific gravity higher than 1.

8. Process in accordance with claim 2 in which said halogenatedhydrocarbon is tetrachlorethane.

9. Process in accordance with claim 2 in which said halogenatedhydrocarbon is p-dichlorbenzene,

JOHN V. STARR. GUSTAV A. BEISWENGER.

